In a passenger conveyor, a plurality of footsteps, endlessly coupled at a regular interval, are circularly driven while being guided by rails. In a normal operation, the footsteps are driven so that adjacent footsteps have no opening between them to be continuous with each other at portions where passengers ride on. Footsteps may, however, accidentally drop off from the rail, or may be partly taken off in maintenance. In such cases, one or more footsteps become missing at a portion where passengers ride on and an opening arises in footsteps, which creates a wide interval between the adjacent footsteps.
There is a detection device which detects an arising of an opening caused by the loss of a footstep. The detection device has a detection member beneath the footsteps which are moving toward the boarding area, and keeps rollers mounted to the detection member in contact with the footsteps elastically. When there is an opening between the footsteps, the detection member depresses a detection switch by rocking in excess of a predetermined angle. Receiving a signal outputted from the detection switch, an operation control device stops the operation of the passenger conveyor. In this way, an opening is prevented from arising between the footsteps at the boarding area to ensure passenger safety.